Day in Engineering History Archive - June 30

June 30

1879: The California Electric Light Company was organized in San Francisco, becoming the first electric company formed to produce and sell electricity 1905: Albert Einstein published his theory on special relativity, "On the Electrodynamics of Moving Bodies." 1908: An unexplained explosion in Tunguska, Siberia knocked down trees in a 40-mile radius and knocked people unconscious 40 miles away. 1918: Francis Stanley, famous for his Stanley Steamer automobile, died. 1930: The first round-the-world broadcast from the U.S. used a series of short-wave radio relays and took one-eighth of a second. 1946: The first atomic bomb dropped from an airplane over water occurred over the Bikini Atoll onto a target group of 73 scrapped ships. 1948: The invention of the transistor was announced by Bell Laboratory. 1948: The first telephone recording devices were authorized for public use in the U.S., and required a periodic "beep" to alert the users. 1953: The first Corvette rolled off the Chevrolet assembly line (it sold for $3,250). 1961: Dr. Lee de Forest, inventor of the Audion tube, died. 1971: Three cosmonauts aboard Soyuz 11 were found dead inside their spacecraft after it had returned to Earth. 1972: The first leap second time correction was added. 1997: China resumed sovereignty over Hong Kong.